This invention relates generally to apparatus for feeding segmented webs of paper or the like material, such as, for example, computer printout forms, and more particularly to a forward-reverse drive mechanism for controlling the feeding of such material.
With the increased use of computers for storage and retrieval of information, hard copy computer printouts on fan fold or segmented paper webs are becoming more prevalent. The need for providing inexpensive copies of such printouts has also increased. One way to provide an inexpensive copy thereof is through the use of an electrostatic or the like copier. Manually feeding the segments of a computer printout web to the platen of a copier, however, becomes difficult and time-consuming. As such, apparatus for feeding computer forms to the original document platen of an electrostatic or the like copying machine has been made available. With such apparatus, the segmented or fan fold computer form web which is normally folded in accordion fashion so that the individual segments can be stacked, is sequentially unfolded and fed from a first station to the original document platen of the copying machine. From there the web is fed to a second station where it is refolded and stacked. With a computer form feeder of the type described, it is possible to feed the paper so that single segments are indexed to the original document platen automatically in a forward or reverse direction. If it is desired, the operation of the copying machine can be controlled by the operation of the computer form feeder so that each time a segment of the computer printout form is fed to the platen, the copier is operated to make one or more copies of that particular segment.
To be able to transport the computer printout web as described, an efficient drive mechanism must be provided. Such a drive mechanism must be capable of functioning to propel the computer printout web incrementally in both forward and reverse directions, to position precisely successive segments of the web onto the platen as well as in a continuous feed mode when it is desired to copy only selected segments of the web.